Abstract: A mixer configured for releasing large bubbles into wastewater is provided. The mixer can include a central draft tube, an upwardly-extending member surrounding the draft tube, and an accumulator surrounding both the upwardly-extending member and the draft tube. A lower end of the draft tube sidewall may be sealed and not include any openings beneath the lower end of the upwardly-extending member, so as to prevent liquid pumpage through the draft tube. A method for treating wastewater in a system that includes at least one large bubble mixer and at least one fine bubble diffuser is also provided. The large bubble mixer and fine bubble diffuser may be supplied gas independently from one another. The method can include multiple modes of operation wherein gas is either supplied to the mixer, to the diffuser, to neither the mixer or the diffuser, or to both the mixer or the diffuser.

Abstract: A mixer configured for releasing large bubbles into wastewater is provided. The mixer can include a central draft tube, an upwardly-extending member surrounding the draft tube, and an accumulator surrounding both the upwardly-extending member and the draft tube. A lower end of the draft tube sidewall may be sealed and not include any openings beneath the lower end of the upwardly-extending member, so as to prevent liquid pumpage through the draft tube. A method for treating wastewater in a system that includes at least one large bubble mixer and at least one fine bubble diffuser is also provided. The large bubble mixer and fine bubble diffuser may be supplied gas independently from one another. The method can include multiple modes of operation wherein gas is either supplied to the mixer, to the diffuser, to neither the mixer or the diffuser, or to both the mixer or the diffuser.

Abstract: A system and method for aerating and mixing wastewater that includes fine bubble diffusers located at least partially below a large bubble mixer. At least a portion of the gas discharged from the fine bubble diffusers is captured by the large bubble mixer and is reused by the large bubble mixer to form and release intermittent large bubbles. Prior to being captured by the large bubble mixer, the gas discharged by the fine bubble diffusers can aerate the wastewater. The large bubble mixer includes an accumulator that, upon becoming filled with gas, generates and releases a large bubble. Upon discharge from the large bubble mixer, the large bubbles generated therein may separate into a plurality of coarse bubbles for providing additional oxygen transfer and mixing of the wastewater. The system may include supply lines for supplying gas only to the fine bubble diffuser.

Abstract: A system and method for aerating and mixing wastewater that includes fine bubble diffusers located at least partially below a large bubble mixer. At least a portion of the gas discharged from the fine bubble diffusers is captured by the large bubble mixer and is reused by the large bubble mixer to form and release intermittent large bubbles. Prior to being captured by the large bubble mixer, the gas discharged by the fine bubble diffusers can aerate the wastewater. The large bubble mixer includes an accumulator that, upon becoming filled with gas, generates and releases a large bubble. Upon discharge from the large bubble mixer, the large bubbles generated therein may separate into a plurality of coarse bubbles for providing additional oxygen transfer and mixing of the wastewater. The system may include supply lines for supplying gas only to the fine bubble diffuser.

Abstract: A wastewater treatment system and method are provided to nitrify and remove residual CBOD and solids from a secondary wastewater pretreatment system. The system can be configured to maintain a population of nitrifying bacteria year-round, and is therefore capable of providing a high nitrification rate during prolonged periods of cold weather.

Abstract: A wastewater treatment system and method are provided for preventing or reducing ammonia rebound during periods of warming weather. The system may be operated in first and second modes of operation. During the first mode of operation, wastewater may pass directly from a reactor to a partial mix cell and then to a polishing cell. During the second mode of operation, which typically occurs during a springtime warmup period, wastewater is retained within the partial mix cell until sludge and biosolids therein are substantially digested, while wastewater exiting the reactor is temporarily directed to the polishing cell, thereby bypassing the partial mix cell. Upon digestion and stabilization of the sludge and biosolids in the partial mix cell, the system may return to the first mode of operation. Sludge and biosolids may optionally be removed from the reactor during the first and second modes of operation.

Abstract: A diffuser membrane and a method for manufacturing the same are provided. In the method for manufacturing, a first material is heated and extruded to form a base layer and a second material is heated and extruded to form a coating layer. The base layer and coating layer may be extruded substantially simultaneously in a coextrusion process. Accordingly, the coating may be applied to the base layer in a manner that optimizes the bonding between the two layers and provides the ability to control the thickness of the coating layer. Alternatively, the base layer is formed initially and the coating layer is subsequently formed thereover. The first and second materials have differing properties. The first material may comprise polyurethane and the second material may comprise polyurethane and PTFE.

Abstract: A diffuser membrane and a method for manufacturing the same are provided. In the method for manufacturing, a first material is heated and extruded to form a base layer and a second material is heated and extruded to form a coating layer. The base layer and coating layer may be extruded substantially simultaneously in a coextrusion process. Accordingly, the coating may be applied to the base layer in a manner that optimizes the bonding between the two layers and provides the ability to control the thickness of the coating layer. Alternatively, the base layer is formed initially and the coating layer is subsequently formed thereover. The first and second materials have differing properties. The first material may comprise polyurethane and the second material may comprise polyurethane and PTFE.

Abstract: A system and method for treating wastewater in a reactor of the system at or below a predetermined flow rate and at or above a predetermined temperature is provided. Incoming wastewater in excess of the predetermined flow rate is directed to an equalization basin for storage. Wastewater stored in the equalization basin is directed to the reactor when (a) the temperature of such stored wastewater is equal to or greater than the predetermined temperature and (b) wastewater is received by the system at a rate less than the predetermined flow rate. The method also involves the step of repurposing a lagoon basin of an existing lagoon system to function as the equalization basin. The system may further include an integrated control system for directing wastewater stored in the equalization basin to the reactor when predetermined conditions are met.

Abstract: A diffuser membrane and a method for manufacturing the same are provided. In the method for manufacturing, a first material is heated and extruded to form a base layer and a second material is heated and extruded to form a coating layer. The base layer and coating layer may be extruded substantially simultaneously in a coextrusion process. Accordingly, the coating may be applied to the base layer in a manner that optimizes the bonding between the two layers and provides the ability to control the thickness of the coating layer. Alternatively, the base layer is formed initially and the coating layer is subsequently formed thereover. The first and second materials have differing properties. The first material may comprise polyurethane and the second material may comprise polyurethane and PTFE.

Abstract: A wastewater treatment system is provided having a reactor, first and second bio media and an aeration system. The first bio medium is located proximate an inlet end of the reactor and extends vertically between a top water level and the reactor's floor. The second bio medium is located proximate an outlet end of the reactor and extends vertically between a bottom water level and the reactor's floor. The media are adapted for retaining solids within the reactor as clarified water is withdrawn after treatment. The first bio media is further adapted to act as a baffle thereby causing wastewater to flow generally uniformly into a primary reactor zone. The aeration system includes a plurality of diffusers, some of which may be located adjacent or underneath the bio media and are adapted for promoting the shaking the bio media when activated in order dislodge excessive biomass therefrom.

Abstract: A wastewater treatment system and method are provided for preventing or reducing ammonia rebound during periods of warming weather. The system may be operated in first and second modes of operation. During the first mode of operation, wastewater may pass directly from a reactor to a partial mix cell and then to a polishing cell. During the second mode of operation, which typically occurs during a springtime warmup period, wastewater is retained within the partial mix cell until sludge and biosolids therein are substantially digested, while wastewater exiting the reactor is temporarily directed to the polishing cell, thereby bypassing the partial mix cell. Upon digestion and stabilization of the sludge and biosolids in the partial mix cell, the system may return to the first mode of operation. Sludge and biosolids may optionally be removed from the reactor during the first and second modes of operation.

Abstract: A system and method for treating wastewater in a reactor of the system at or below a predetermined flow rate and at or above a predetermined temperature is provided. Incoming wastewater in excess of the predetermined flow rate is directed to an equalization basin for storage. Wastewater stored in the equalization basin is directed to the reactor when (a) the temperature of such stored wastewater is equal to or greater than the predetermined temperature and (b) wastewater is received by the system at a rate less than the predetermined flow rate. The method also involves the step of repurposing a lagoon basin of an existing lagoon system to function as the equalization basin. The system may further include an integrated control system for directing wastewater stored in the equalization basin to the reactor when predetermined conditions are met.

Abstract: An aeration system for treating liquid contained in a vessel is provided. The aeration system includes a header pipe and a plurality of lateral pipes coupled to the header pipe. The lateral pipes each have one or more tubular diffuser membranes sleeved therearound. Also provided is a coupling for sealingly joining end portions of two adjacent pipes is provided. The coupling includes two saddle sections and a deformable gasket extending between the pipes. The coupling is adapted for enabling one pipe to be removed and replaced from a series of pipes without substantially moving any adjacent pipes.

Abstract: A wastewater treatment system is provided having a reactor, first and second bio media and an aeration system. The first bio medium is located proximate an inlet end of the reactor and extends vertically between a top water level and the reactor's floor. The second bio medium is located proximate an outlet end of the reactor and extends vertically between a bottom water level and the reactor's floor. The media are adapted for retaining solids within the reactor as clarified water is withdrawn after treatment. The first bio media is further adapted to act as a baffle thereby causing wastewater to flow generally uniformly into a primary reactor zone. The aeration system includes a plurality of diffusers, some of which may be located adjacent or underneath the bio media and are adapted for promoting the shaking the bio media when activated in order dislodge excessive biomass therefrom.

Abstract: A single-layer diffuser membrane constructed of first and second compounds. The first compound has structural and flexibility properties suitable for applying air to wastewater through a plurality of perforations formed through the membrane and the second compound is suitable for inhibiting fouling of the membrane. The first compound may comprise polyurethane and the second compound may comprise polytetrafluoroethylene. The concentration of the second compound within the membrane may be between about 3.0 vol. % and 20.0 vol. %. The second compound may be dispersed adjacent the perforations to inhibit fouling of the perforations. Another aspect of the present invention relates to the method for constructing the membrane. Upon the mixing of the first and second compounds, the mixed composition may be formed into a membrane through, for example, an extrusion process or a molding process. Perforations may be created either during or after the forming of the membrane.

Abstract: A wastewater treatment system is provided having a reactor, first and second bio media and an aeration system. The first bio medium is located proximate an inlet end of the reactor and extends vertically between a top water level and the reactor's floor. The second bio medium is located proximate an outlet end of the reactor and extends vertically between a bottom water level and the reactor's floor. The media are adapted for retaining solids within the reactor as clarified water is withdrawn after treatment. The first bio media is further adapted to act as a baffle thereby causing wastewater to flow generally uniformly into a primary reactor zone. The aeration system includes a plurality of diffusers, some of which may be located adjacent or underneath the bio media and are adapted for promoting the shaking the bio media when activated in order dislodge excessive biomass therefrom.

Abstract: A flexible diffuser membrane used in aeration/mixing of wastewater is impregnated with biocide and treated with fluorine or another halogen gas which forms a barrier inhibiting migration of the biocide out of the membrane. Another aspect of the invention involves cleaning a diffuser membrane with a halogen and then coating the membrane with PTFE or polyurethane.

Abstract: A wastewater treatment system is provided having a reactor, first and second bio media and an aeration system. The first bio medium is located proximate an inlet end of the reactor and extends vertically between a top water level and the reactor's floor. The second bio medium is located proximate an outlet end of the reactor and extends vertically between a bottom water level and the reactor's floor. The media are adapted for retaining solids within the reactor as clarified water is withdrawn after treatment. The first bio media is further adapted to act as a baffle thereby causing wastewater to flow generally uniformly into a primary reactor zone. The aeration system includes a plurality of diffusers, some of which may be located adjacent or underneath the bio media and are adapted for promoting the shaking the bio media when activated in order dislodge excessive biomass therefrom.

Abstract: A diffuser membrane and a method for manufacturing the same are provided. In the method for manufacturing, a first material is heated and extruded to form a base layer and a second material is heated and extruded to form a coating layer. The base layer and coating layer may be extruded substantially simultaneously in a coextrusion process. Accordingly, the coating may be applied to the base layer in a manner that optimizes the bonding between the two layers and provides the ability to control the thickness of the coating layer. Alternatively, the base layer is formed initially and the coating layer is subsequently formed thereover. The first and second materials have differing properties. The first material may comprise polyurethane and the second material may comprise polyurethane and PTFE.